The abundant short and long grasses of the Serengeti plains support the large number of grazing animals that exist in the park. However it is due to the "grazing succession" that makes their co-existence possible. The elephants, hippos, rhinos and buffaloes are considered heavy grazers and as they wander through the park they continually eat and trample the large coarse grasses. This enables the light grazers like zebra, topi and wildebeest to eat the vegetation as it is altered by the heavy grazers. The light grazers alter the vegetation for the lightest herbivores like gazelles and warthogs. Finally these animals are followed by the carnivores like the lion, hyena, cheetah, leopard who are their predators.

The wet season is from December to March (winter months) and is considered the best time to come to the Serengeti National Park. During this time there are large numbers of wildlife concentrated in the southern region, near Ngorongoro. May or June (spring months) is when the immense herds of wildebeest and zebra begin their circuitous migration. The dry season begins and they head to the western regions of the park in search of water and food. From July to November (summer months) the animals are spread throughout the park as they continue their search for food and water. Some of the animals head north and others north-east to the rivers. Eventually they concentrate in the Massai Mara National Reserve in Kenya. When the food supply is exhausted they head south and continue along the eastern region of the park completing their annual migration.